US Robotics

Posted on 1998-07-20
Last Modified: 2013-12-27
When I first turn on my external sportster 33.6 modem, the TR and CS lights flash and just keep flashing. It happens about once every second or two. It was working fine until last night.

Does this mean the modem is fried?
Question by:flfmdll
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions

Expert Comment

ID: 1147103
Connect to the COM port that your modem is attached to, via HyperTerminal. Then write AT&F1. IF that does not work try ATZ3.

Author Comment

ID: 1147104
I did try using the dip switch in the back to reset to factory defaults. If I did it right, that had no effect. I'll give this a try and get back with you. Thanks.


Expert Comment

ID: 1147105
Something to consider:
Resetting the dip switches will probably then cause the modem to be unrecognized by the computer.
If it won't respond using the default switch settings, go back to the last settings that worked and try the AT&F1 command.

Simple, centralized multimedia control

Watch and learn to see how ATEN provided an easy and effective way for three jointly-owned pubs to control the 60 televisions located across their three venues utilizing the ATEN Control System, Modular Matrix Switch and HDBaseT extenders.


Author Comment

ID: 1147106
Ralph, just so you know, I only reset it via the dip switch after the lights started flashing. Also, the lights the flash whether or not it is connected to the computer (RS232 cable).

Expert Comment

ID: 1147107
Check your documentation for the modem.  Perhaps the flashing LEDs are indicating some type of error code.


Author Comment

ID: 1147108
I tried looking at the documentation. I don't see anything about flashing lights that does NOT relate to data being transferred. I know there is no data being transferred.

By the way, the modem is at home. I'm at work. So I can't try the software reset until I get home.

But thanks,

Expert Comment

ID: 1147109
Let us know what you find........


Expert Comment

ID: 1147110
There is a high probability that the timed flashing of the modem lights indicates a failure code... or at the very least a modem failure that in-turn creates a very confused modem.
The TR light indicates, in a working modem, Data terminal ready..that is..the computer has set this handshake line to indicate it is ready for a data transfer.
The CR light is the Clear to send handshake signal.

I tied, in vain, to search for Modem light error codes for the USR. If your modem is still under warrenty I would suggest contacting the USR support hotline(847)982-5151.

Good Luck,

John C. Cook

Accepted Solution

joe_massimino earned 30 total points
ID: 1147111
Does this modem still work to connect as usual?  If not, it is broke, and when you call USR for service they will tell you what the flashing means.  If the modem does connect fine, then you could issue a command to reset the modem to the factory configuration.  
Some modems, USR included, flash one LED to indicate the modem is set to FAX mode. Two flashing LEDS are possible also.
I imagine you can solve this very easily by answering my question. If the modem does not operate, and issuing a factory reset does not help, the next step would be to check you com port on another serial device, (another modem?) If the com port checks good it's time to contact USR if you want to persue getting it repaired.

Featured Post

Free Tool: ZipGrep

ZipGrep is a utility that can list and search zip (.war, .ear, .jar, etc) archives for text patterns, without the need to extract the archive's contents.

One of a set of tools we're offering as a way to say thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
What network switches should I use for Fiber WAN project 4 36
Resource cost of NAT vs routing 3 89
Resource timeout across a VPN 9 70
Need to cut my Verizon home cost 3 65
Hi there, This article summarizes what you need if you are going to set up your home or small business Network Attached Storage (NAS) to be accessible from the internet. Of course there are configuration differences based on your NAS or router ma…
Arrow Electronics was searching for a KVM  (Keyboard/Video/Mouse) switch that could display on one single monitor the current status of all units being tested on the rack.
Nobody understands Phishing better than an anti-spam company. That’s why we are providing Phishing Awareness Training to our customers. According to a report by Verizon, only 3% of targeted users report malicious emails to management. With compan…
A short tutorial showing how to set up an email signature in Outlook on the Web (previously known as OWA). For free email signatures designs, visit If you want to manage em…

751 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question